1. Field of the Invention
The present invention relates to a pressure checker which allows easy visual checking of whether the pressure in a liquid pipe is equal to a predetermined pressure.
2. Description of the Related Art
At present, high- and low-pressure fluids are delivered to homes, factories, and laboratories in a variety of applications. These high- and low-pressure fluids must be maintained at a minimum pressure, depending on their use. For example, when the pressure of a fluid in a gas cylinder is below a predetermined pressure, the gas cylinder must be quickly exchanged. In addition, when the pressure of a pressurized fluid supplied through a small fluid pipe is below a predetermined pressure, the amount of stored fluid must be increased in order to increase the pressure of the fluid in the storage tank.
In order to confirm a change in pressure of a supplied fluid, a pressure gauge is conventionally used.
It is known that some application fields which conventionally use pressure gauges do not always require a pressure gauge. However, it is appreciated for the sake of safety that a time for exchanging an object, such as a gas cylinder, or remaining amount of fluid therein can be found out, or that a fluid pressure can be checked in a simple way. Therefore, a demand has arisen for developing a gauge which allows accurate and easy confirmation of a change in pressure of fluid without the conventional gauge.